A powerholder of a power of appointment that is not presently exercisable may contract to exercise or not to exercise the power only if the powerholder: (1) is also the donor of the power; and (2) has reserved the power in a revocable trust.
Power To Contract -- Power Of Appointment Not Presently Exercisable
Mont. Code Ann. § 72-7-406, under Disclaimer on Release -- Contract to Appoint or Not to Appoint.
Mont. Code Ann. § 72-7-406